SmoothStreaming: Replace variant bitrate/start_time placeholders

Issue: #2447

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147358615

library/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/manifest/SsManifest.java

@@ -128,8 +128,10 @@ public ProtectionElement(UUID uuid, byte[] data) {
    */
   public static class StreamElement {
 
-    private static final String URL_PLACEHOLDER_START_TIME = "{start time}";
-    private static final String URL_PLACEHOLDER_BITRATE = "{bitrate}";
+    private static final String URL_PLACEHOLDER_START_TIME_1 = "{start time}";
+    private static final String URL_PLACEHOLDER_START_TIME_2 = "{start_time}";
+    private static final String URL_PLACEHOLDER_BITRATE_1 = "{bitrate}";
+    private static final String URL_PLACEHOLDER_BITRATE_2 = "{Bitrate}";
 
     public final int type;
     public final String subType;
@@ -216,9 +218,13 @@ public Uri buildRequestUri(int track, int chunkIndex) {
       Assertions.checkState(formats != null);
       Assertions.checkState(chunkStartTimes != null);
       Assertions.checkState(chunkIndex < chunkStartTimes.size());
+      String bitrateString = Integer.toString(formats[track].bitrate);
+      String startTimeString = chunkStartTimes.get(chunkIndex).toString();
       String chunkUrl = chunkTemplate
-          .replace(URL_PLACEHOLDER_BITRATE, Integer.toString(formats[track].bitrate))
-          .replace(URL_PLACEHOLDER_START_TIME, chunkStartTimes.get(chunkIndex).toString());
+          .replace(URL_PLACEHOLDER_BITRATE_1, bitrateString)
+          .replace(URL_PLACEHOLDER_BITRATE_2, bitrateString)
+          .replace(URL_PLACEHOLDER_START_TIME_1, startTimeString)
+          .replace(URL_PLACEHOLDER_START_TIME_2, startTimeString);
       return UriUtil.resolveToUri(baseUri, chunkUrl);
     }